Trashman & Ultrasonic
Ultrasonic
Hey, I hear you’re all about salvaging, right? I’ve been thinking about turning some old copper wiring into a high‑frequency audio circuit—pure 40kHz tones running through a vintage speaker.
Trashman
Nice idea, but 40kHz on a vintage speaker? Those tubes can’t even handle that. Get a proper piezo or a cheap RF amplifier. Don’t waste copper on a thing that’ll just hiss. If you’re going to salvage, fix something that actually works. And remember, duct tape works for a lot of things, so keep it handy.
Ultrasonic
Got it, but a vintage tube can still survive 40 kHz if you keep the load low and use a proper impedance match. I’d strip a single‑turn copper lead, route it through a clean, straight cable, and let the tube do its thing—no fancy RF amp needed. Duct tape is fine for mounting, but not in the signal chain. If you want pure, subtle high‑frequency decay, the old gear is the only way to hear it.
Trashman
You’re going to burn that tube before it even gets to the speaker. Old gear ain’t the solution, it’s the problem. Pull a single‑turn, keep the load low, you’re still gonna hit a lot of noise and a bad match. Grab a cheap crystal oscillator, a piezo driver, or a 40kHz relay. If you’re really into salvaging, use the copper for something practical—maybe a power line filter or a simple LED driver. And for the mounting, duct tape is fine, but don't put it in the signal path. Keep it tidy, keep it working.
Ultrasonic
I hear you about the tube, but if you run a 40kHz spike with a properly wound single‑turn coil and a low‑impedance load, the tube’s cathode can actually handle it—just keep the drive level low. Noise will still come from the tube’s own hiss, but you can tame it with a little passive RC filter before the speaker. A crystal oscillator or piezo driver is fine, but it’s the precision of a straight copper path that keeps the phase clean. And yeah, duct tape for mounting is fine—just not in the signal chain. Let’s keep the wires tidy, no stray inductance, and keep the reverb tail pure.
Trashman
Sure, but if you do it you’ll end up with a hiss and a blown tube. Keep the drive low, use a proper choke, and maybe just salvage the copper for a real low‑pass filter instead of trying to make a 40kHz tone. And remember, duct tape is fine on the frame, not the signal. Keep it simple, keep it working.
Ultrasonic
Sounds good. I’ll use a ferrite choke, keep the drive low, and run the copper as a clean low‑pass path. Duct tape on the frame, not the signal. Thanks for the heads‑up.